Safety lock for medicine cabinet doors



March 6, 1962 R. LUIKART n, ETAL 3,023,601

SAFETY LOCK FOR MEDICINE CABINET DOORS Filed June 16, 1960 [-76.1

INN-Ill! llll: E

Ru/ph Lu/kar/ZZ' Joseph B. McGaever ATTORNEY rates Calif.

Filed June 16, 1960, Ser. No. 36,632 1 Claim. (Cl. 70-297) Thisinvention relates to a lock or fastener for doors, sliding drawers, andthe like.

A primary object of the invention is to provide a safety door lock formedicine cabinets or the like, designed particularly to prevent childrenfrom gaining access to the cabinet where poisons of various kinds may bestored.

Another object of the invention is to provide a door fastener of theabove-mentioned character which is relatively simple and economical inconstruction, compact and strong and durable.

Still another object is to, provide a safety lock or fastener of thementioned character which is easy to operate by adults but perplexingand substantially impossible to operate by small children withoutknowledge of the workings of the simplified combination mechanism.

Another object is to provide a cabinet door lock which is adjustable andeasy to install adjacent the cabinet door or any other door which it isdesired to secure against opening by children.

.Other objects and advantages of the invention will be apparent duringthe course of the following description.

In the accompanying drawings, forming a part of this application, and inwhich like numerals are employed to designate like parts throughout thesame,

FIGURE 1 is a front elevation of a bathroom medicine cabinet or the likeequipped with the safety door lock according to the present invention,

FIGURE 2 is a plan view of the lock on an enlarged scale partly insection,

FIGURE 3 is an enlarged front elevation of the lock and associatedelements,

FIGURE 4 is a vertical section taken on line 44 of FIGURE 3,

FIGURE 5 is a vertical section taken on line 5-5 of FIGURE 3,

FIGURE 6 is a central horizontal section through the lock,

FIGURE 7 is a rear side elevation of the lock partly in section.

In the. drawings, wherein for the purpose of illustration is shown apreferred embodiment of the invention, the numeral 10 designates avertical wall upon which is mounted a conventional medicine cabinet orthe like having the usual horizontally swingable door 11 hinged theretoin a conventional manner.

The lock or fastener proper for the door 11, according to the invention,is indicated generally by the numeral 12 in FIGURE 1, and the lock isinstalled upon the wall 10 adjacent to the swingable edge of the door11, as indicated in the drawings.

The lock 12' comprises a generally cylindrical base or mounting member13, preferably having an enlarged rear flange 14 engageahle with thewall 10, and preferably provided upon its rear face with a plurality ofspaced prongs 15 which penetrate the wall surface to prevent the base 13from turning. The base 13 has a forwardly opening central screw-threadedbore 16, having a rear undercut portion 17, and a rearwardly openingtapered bore 18, adapted to receive the head of a wood screw 19, or thelike, utilized for rigidly securing the base upon the wall 10 in theselected position.

A relatively stationary cylindrical head 12 is provided,

atent EQQ having a central cylindrical bore 21 formed therethrough, andincluding a rearwardly projecting externally screw-threaded tubularextension 22 formed integral therewith. The tubular extension 22 isadapted to have screwthreaded engagement within the screw-threaded bore16, and a locking nut 23 and lock washer 24 on the extension 22 serve tolock the extension and head in the selected axially adjusted positionrelative to the fixed base 13.

The bore 25 of tubular extension 22 is somewhat larger than the headbore 21, and a lateral shoulder 26 is formed at the rear end of the bore21, where the same communicates with the enlarged bore 25.

An elongated generally rectangular locking member or bar 27 is disposedforwardly of the cabinet door 11 and adjacent the forward face of thehead 12. The width of the locking bar or swinging bolt 27 is preferablysubstantially equal to the diameter of the head 12 and the locking barextends for substantial distances on opposite sides of the head so as tobe capable of overlapping engagement with the edge portion of thecabinet door 11.

An axially extending screw 28 has a cylindrical head portion 29 engagingrotatably within the bore 25 of extension 22, and a reduced cylindricalshank portion 30 engaging rotatably within the bore 21 of the head 12.The head of the screw 28 has a socket 31 to facilitate tightening thescrew. A forward reduced screw-threaded extension 32 on the screw 28 hasscrew-threaded engagement Within a centrally located screw-threadedopening 33 in the rear face of the locking bar 27, at the longitudinaland transverse centers thereof. The screw 28 has a shoulder 34 forpositive engagement with the rear face of the locking bar 27, so thatthe locking bar may be rigidly secured to the screw 28 forrotationthere: with as a unit relative to the stationary head 12. andits extension 22.

The head 12 is provided in its forward face with four preferablyequidistantly spaced deep cylindrical recesses 35, FIGURES 4 and 5, andthese recesses are disposed opposite the central portion of the lockingbar 27 and have the spaced arrangement indicated in FIGURE 3. Companiondeep cylindrical recesses 36 are formed in the rear face of the lockingbar 27, which rear face substantially abuts the forward. face of thehead 12 slid: ably. When the locking bar 27 is arrangedhorizontally asin FIGURE 3, or vertically as indicated'by dotted lines in FIGURE 1, therecesses 35 and 36 are in registration as indicated clearly in FIGURES4.21miv 5. In all other angular positions of the locking bar 27, therecesses 35 and 36 are out of registration.

With continued reference to FIGURES 3 through 6, diagonally oppositepairs of the recesses 35 contain relatively long coil springs 37, andthe corresponding diagonally opposite recesses 36 contain relativelyshort reciprocatory plungers 38, havingreduced operating pin extensions39, extending slidably through small openings in the forward face oflocking bar 27. The operat: ing extensions 39 project forwardly of thelocking bar 27 so as to be engageable by the fingers of the personoperating the lock. Lock balls 40 are interposed between the springs 37and plungers 38, Within the bores 35 and 36 and these lock ballsnormally span the entrance portions of the registering bores 35 and 36adjacent the opposed faces of the head 12 and locking bar to lock thelatter against rotation relative to the head 12.

The other diagonally opposite pair of recesses 35 contain relativelyshort coil springs 41 and balls 42, as shown, and the correspondingdiagonally opposite recesses 36 contain relatively long reciprocatoryplungers 43 having forward reduced operating pin extensions 44,

projecting forwardly of the locking bar 27, and extending slidablythrough small openings in the forward face of the locking bar, FIGURES 4and 5.

The balls 42 are normally maintained bodily within their recesses 35,and the plungers 43 are normally bodily within their recesses 36, sothat these plungers normally have no locking influence upon the lockingbar 27 and head 12.

Outwardly of the head 12 and near the ends of the locking bar 27, thesame is provided in its rear face with additional spaced pairs of deepcylindrical recesses 45, containing coil springs 46 and forwardlyprojecting dummy operating pin elements 47, having the same appearanceas the previously described pin elements 39 and 44. The pin elements 47have enlarged heads 4 ,8 within the recesses 45, FIGURE 7. The spacingof the recesses 46 and pin elements 47 is as shown in FIGURE 3, and allof the operating pin elements are arranged in two parallel longitudinalrows along the locking bar 27 and equidistantly spaced, as in FIGURE 3.Resilient pads 49 are secured in any suitable manner to the rear face ofthe locking bar 27 near the ends of the latter and on opposite sides ofthe head 12. These pads serve to maintain the light coil springs 46within the recesses 45, and the pads 49 are engageable firmly againstthe front face of the cabinet door 11 for securing the same, withoutscratching or marring the door. The endmost pairs of pin elements 47have no effect whatsoever upon the operation of the lock and are merelya subterfuge intended to bewilder children who may attempt to open themedicine cabinet door.

To unlock and open the door 11, when the locking bar 27 is in theposition shown in FIGURES 2 and 3, it is necessary to depress the twodiagonally opposite pin extensions 39, until they are flush with thefront face of the locking bar 27. This will shift the locking balls 40bodily into their recesses 35, and the inner ends of the plungers 38will be flush with the meeting faces of the locking bar and head 12.When this condition is achieved, none of the plungers or balls areexerting any locking influence, and the locking bar 27 may be turned tothe vertical position shown in dotted lines in FIGURE 1 to release thedoor 11. When the locking bar is returned to the horizontal positionshown in full lines in FIGURE 1, the locking balls 40 will automaticallyreturn to their active or locking positions due to reregistration of theparticular recesses 35 and 36.

Should the child depress all four of the central pin extensions 39 and44, which is a natural tendency, this will not unlock the cabinet door,because the depression of the plungers 43 will cause these plungers toenter the recesses 35 and span the opposed faces of the locking bar 27and head 12, and this will lock the locking bar, despite the fact thatthe simultaneous depression of the plunger-s 38 will unlock the lockingbar. Thus, it is possible to unlock the cabinet door only by depressingthe two diagonally opposite pinextensions 39 simultaneously. Depressingonly one of the pin extensions 39 will not unlock the cabinet door,asshould be obvious, depressing one or both pin extensions 44 will notunlock the cabinet door, and depressing all of the pin extensions 39 and44 simultaneously will not unlock the cabinet door, as stated. The dummypin extensions 47 have no effect on the lock as previously stated.

To install the lock, the base 13 is first secured to the wall with thescrew 19. The locking bar 27 is then tightly secured to the screw 28after the latter is introinvention can also be utilized in connectionwith sliding drawers or the like. When used in connection with drawersthe mounting member 13 would be mounted adjacent one edge of the draweror could be readily mounted on the fixed bar above a drawer or on thefixed bar between two drawers, so that the rectangular locking membercan be pivoted into overlapping engagement with an edge portion orportions of the drawer or drawers, respectively, to maintain the same ina locked condition, thus preventing access thereto by small children.

It is to be understood that the form of the invention herewith shown anddescribed is to be taken as a preferred example of the same, and thatvarious changes in the shape, size and arrangement of parts may beresorted to, without departing from the spirit of the invention or thescope of the subjoined claim.

Having thus described our invention, we claim:

A lock device to prevent access by children to medicine cabinets and thelike, comprising a base element for attachment to a fixed support nearthe movable edge of a swinging medicine cabinet door, a relativelystationary head secured adjustably to the base element and positionablenear the outer face and said movable edge of said door, a generallyrectangular swinging bolt pivoted to said head in opposed substantiallycontacting relation with the outer face of the head and being elongatedand extending upon opposite sides of the head and including end portionswhich may overlap the outer face of said door to secure the latter, saidhead and bolt provided in their opposed faces with first and seconddiagonal pairs of recesses adapted to register when the bolt is inoverlapping relation to the front face of said door, a first pair ofplungers in the first diagonal pair of recesses of the bolt andextending through the forward side of the bolt and operable from theforward side of the bolt, resilient detents in the correspondingdiagonal pair of recesses of the head normally spanning the opposedfaces of the head and bolt to lock the same against relative rotationand released by depression of said first diagonal pair of plungers, asecond pair of plungers in the second diagonal pair of recesses of thebolt extending through and operable from the forward side of the bolt,second resilient detents in the second diagonal pair of recesses of thehead normally releasing the head and bolt for relative rotation butlocking the latter when the second plungers are depressed, and dummypairs of plungers in the bolt outwardly of the diagonal pairs and insubstantial lateral alignment therewith and projecting forwardly of thebolt near the ends of the bolt and having the same appearance as thediagonal plungers to confuse children, the arrangement being such thatthe bolt may be turned to cabinet door releasing position only aftersimultaneous depression of the first diagonal pair of plungers of thebolt.

References Cited in the file of this patent UNITED STATES PATENTS259,523 Gage June 13, 1882 1,530,092 Robertson Mar. 17, 1925 1,608,539Wetherell Nov. 30, 1926 2,643,905 Hummer June 30, 1953

